code: def gen_L(n: int, *shape: int) -> AnyNDArray:
      return np.array([np.tril(rng.randn(*shape)) for _ in range(n)])
  
imports: from typing import Collection, Optional
  import numpy
  import pytest
  import tensorflow
  from check_shapes import ShapeChecker, check_shapes
  from numpy.testing import assert_allclose
  import gpflow
  from gpflow.base import AnyNDArray, MeanAndVariance
  from gpflow.conditionals import conditional, uncertain_conditional
  from gpflow.config import default_float
  from gpflow.mean_functions import Constant, Linear, MeanFunction, Zero
  from gpflow.quadrature import mvnquad
  from gpflow.utilities import training_loop
label_desc: Use image node_id 1 for calling a global function with example usage: gen_L(n) and returns: np